Question

chemistry

Answer 1

@vocaloid

Answer 2

For these types of problems, assume you have 100g of the compound

75.3% zinc ---> becomes 75.3% * 100g, or 75.3g Zinc
same logic with 24.5% oxygen ---> 24.5g O2 (remember, oxygen by itself exists as O2 not just O)

divide each mass by the appropriate molar mass

now, you'll have moles of each compound. write the formula based on the moles.

Answer 3

actually sorry just use O not O2 for oxygen

Answer 4

7530?

Answer 5

75.3 divided by 65.38

Answer 6

ah sorry just had to refresh myself on how to do this, I missed an important step

75.3g Zinc / 65.38g/ mol = 1.152 moles Zinc
24.5g Oxygen / 15.99g/mol = 1.531 moles Oxygen

we take the lower number (1.152 moles Zinc) and divide

1.152 moles zinc / 1.152 moles zinc = 1 Zn
1.531 moles oxygen/1.15 moles zinc = 1.32 O

this means our ratio is 1 Zn to 1.32 O. we can round 1.32 down to 1 to get a 1:1 ratio of Zn to O, meaning ZnO is our formula

Answer 7

ZnO is the answer?

Answer 8

yes

Answer 9

couldnt you have easily just connect Zn zinc and O oxygen together making ZnO without the equations?

Answer 10

No. Different compounds have different ratios of atoms.

For example, Iron can have different charges like +3 or +2, so if you have iron oxide, you can't just put iron + oxygen together because you have different ratios of iron/oxygen based on charge.

Answer 11

it says its wrong

Answer 12

alright

if your mole numbers are too far away from integers, you can multiply by whole numbers


75.3g Zinc / 65.38g/ mol = 1.152 moles Zinc
24.5g Oxygen / 15.99g/mol = 1.531 moles Oxygen

we can multiply both by 2 to get 2.3 moles Zinc and 3.06 moles Oxygen, so they might want Zn2O3 instead?

Answer 13

Zinc is only supposed to have a +2 charge and oxygen almost always has a -2 charge, which is why I went for ZnO initially

Answer 14

lower 2 and 3?

Answer 15

yeah they need to be subscripts

Answer 16

the answer is Zn3O4

Answer 17

ok, yeah now I see it

75.3g Zinc / 65.38g/ mol = 1.152 moles Zinc
24.5g Oxygen / 15.99g/mol = 1.531 moles Oxygen

1.152 moles Zn/ 1.152 = 1 mol Zinc
1.531 moles O/1.152 = 1.329 mol O

they want to multiply both by **3** to get 3 mol Z and 4 mol O

Answer 18

ok thanks